This invention relates to apparatus and method for cutting a channel box for a fuel assembly of a nuclear reactor, and more particularly to apparatus for cutting a channel box which is easy to handle and operate.
The core of a nuclear reactor is composed of fuel assemblies. Each fuel assembly includes a cylindrical member for enclosing a plurality of fuel rods containing fissionable material. The cylindrical member for a fuel assembly of a boiling-water reactor is generally referred to as a channel box.
The channel box for a spent fuel assembly withdrawn from the core of a boiling-water reactor is removed from the fuel assembly for storage. However, since the channel box is hollow, a large space is required for storing used channel boxes. To eliminate this problem, several systems for channel box reduction and disposal have been proposed.
One of the channel box reduction and disposal systems is disclosed in Japanese Patent Application Laid-open No. 27795/78 (U.S. Ser. No. 717,166 now abandoned). In this system of the prior art, a plurality of superposed perforations are formed in the wall of a channel box to form axially extending cuts in the channel box. Bits and pieces of channel box material removed from the wall for providing the cuts are received in a container. The channel box plates obtained by cutting are inserted into another container, after being moved thereinto by handling tool means. During a channel box cutting operation, the channel box is gripped by the handling tool means suspended from a hoist. Thus, difficulties have been experienced in the handling and disposal of channel box plates and debris in the prior art method described hereinabove.